Any webcam with a circular form-factor (Logitech Quickcam, Microsoft Lifecam, etc). So named for the proliferation of (soft-core) and (hard-core) (camgirl) porn sites that arose once high speed internet and webcams both became commonplace.

"Dude, your girlfriend got a pornball? I'd be worried, man. Maybe you only get to see her naked from behind a paygate from now on?"